The present invention generally relates to an orthopedic resistance device, and specifically to a device which applies resistance to the knee in one direction and allows relatively free movement of the knee in the opposite direction.
Dysfunction of the knee joint is often a result of abnormalities caused by disease, trauma, or mechanical degradation of the anatomic structures of the knee. The abnormalities cause the knee to mechanically malfunction requiring corrective surgery or therapy. A common result of intraoperative trauma is the introduction of soft tissue constrained joint contractures of varying severity. Various dynamic knee braces are available to provide support and rehabilitation to a damaged knee. Dynamic braces are designed to improve the range of motion over which a knee can flex or extend by applying a constant torque to the knee. However, knee abnormalities can also cause muscular imbalance (poorly coordinated muscular activity) which is not corrected by a dynamic brace.
The anatomic structures of the knee may be altered sufficiently that changes in neuromuscular "motor pathways" may be needed to regain normal, pain free function. Without proper rehabilitation, the neuromuscular motorpathways adapt very slowly to the altered structures thus creating muscular imbalance. While the flexibility of the knee can be rehabilitated using dynamic knee braces, the muscular imbalance may not be corrected and the knee is left with good flexibility but poorly coordinated muscular activity. The result is a knee with full movement yet pain and instability when moved in certain directions.
Neuromuscular re-education is a rehabilitation technique-which accelerates motor pathway development by temporarily altering the amplitude and timing of forces upon the musculoskeletal structures thus altering the amplitude and timing of muscle use in performing physical motion. It is evident that there is a need for applying neuromuscular re-education of the knee via a device which imposes the appropriate musculoskeletal stimuli to the structures of the knee, specifically throughout flexion. In addition, a device which induces properly imposed forces resisting motion of the knee joint in flexion will help to properly realign the musculoskeletal structures of the knee thus providing support and alleviating pain which further accelerates the rehabilitation process. Unlike existing dynamic braces, the device would apply substantial resistance to the knee only through flexion and not through extension.